{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T22:21:01Z","timestamp":1767046861447,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,24]],"date-time":"2024-04-24T00:00:00Z","timestamp":1713916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"],"award-info":[{"award-number":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"]}]},{"name":"National Natural Science Foundation of China","award":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"],"award-info":[{"award-number":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"]}]},{"name":"CAS-CSIRO Partnership Joint Project","award":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"],"award-info":[{"award-number":["SQ2023YFE0201365","2023YFB3608800","2023YFE0206400","62171442","62275264","172511KYSB20210008"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we present a novel three-dimensional (3D) coupled configuration of piezoelectric micromachined ultrasound transducers (pMUTs) by combing a curved and an annular diaphragm for transmit performance optimization in biomedical applications. An analytical equivalent circuit model (EQC) is developed with varied excitation methods to incorporate the acoustic\u2013structure coupling of the curved and annular diaphragm-coupled pMUTs (CAC-pMUTs). The model-derived results align well with the reference simulated by the finite element method (FEM). Using this EQC model, we optimize the key design parameters of the CAC-pMUTs in order to improve the output sound pressure, including the width of the annular membrane, the thickness of the passive layer, and the phase difference of the driving voltage. In the anti-phase mode, the designed CAC-pMUTs demonstrate a transmit efficiency 285 times higher than that of single annular pMUTs. This substantial improvement underscores the potential of CAC-pMUTs for large array applications.<\/jats:p>","DOI":"10.3390\/s24092714","type":"journal-article","created":{"date-parts":[[2024,4,24]],"date-time":"2024-04-24T10:18:36Z","timestamp":1713953916000},"page":"2714","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Curved and Annular Diaphragm Coupled Piezoelectric Micromachined Ultrasonic Transducers for High Transmit Biomedical Applications"],"prefix":"10.3390","volume":"24","author":[{"given":"Yun","family":"Zhang","sequence":"first","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tong","family":"Jin","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zijie","family":"Zhao","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenfang","family":"Yan","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2586-8805","authenticated-orcid":false,"given":"Xinchao","family":"Lu","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4464-4572","authenticated-orcid":false,"given":"Hang","family":"Gao","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4942-5432","authenticated-orcid":false,"given":"Chengjun","family":"Huang","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"eadk8426","DOI":"10.1126\/sciadv.adk8426","article-title":"Wearable bioadhesive ultrasound shear wave elastography","volume":"10","author":"Liu","year":"2024","journal-title":"Sci. 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